One of the biggest problems presently facing the industrial world is the disposal of waste that has been generated and is presently being generated by the various industries. Several techniques were developed in the past to solve the problem. One method involves the use of landfills where the waste is transported for disposal. The disadvantage of that method is that it requires the transportation of the waste to the landfill from areas that are very distant from such landfills, thereby making such disposal uneconomical and oftentimes hazardous to the populated areas through which such waste is transported. Another disadvantage is that in the landfill disposal the waste is merely covered and not permanently contained whereby the problem is passed on to future generations. Waste being disposed in landfills may seep through the ground to subterranean water streams and the waste could be returned to populated areas through the natural water streams. The Environmental Protection Agency has issued regulations prohibiting the prior practice of disposing of liquid waste in landfills and regulating the types of solid waste and solidified waste which can be disposed in certain landfills. Such regulations have made many prior art practices obsolete.
Another method used in the past for the disposal of waste has been chemical treatment. One disadvantage of such treatment is that it is not effective because most of the compounds present in waste, and especially hazardous waste, do not react chemically with other compounds to form non-hazardous compounds. Furthermore, even if the conversion to harmless compounds is possible, such process is uneconomical.
Incineration has also been used in the past as means for the disposal of waste. Incineration, however, is not effective in most applications. Furthermore, incineration processes result in the formation of other undesirable chemicals in the form of ash or gases emitted to the environment. Furthermore, incineration is a very costly process that requires highly sophisticated incineration equipment and requires the transportation of the waste to special locations for the incineration to be performed.
Another method that has been used in the past for disposal of waste has been the process of solidifying the waste by mixing it with sawdust, various pozzolanic materials and polymeric substances. One disadvantage of such methods is their inability to adequately solidify liquid or sludge-type waste. Another disadvantage is that several pozzolanic materials used in the past have not been shown to be effective because of their physical or chemical properties. Attempts, for example, in the past to solidify waste with Portland cement produced a solid product which was very permeable, porous, subject to leaching and deficient in mechanical strength. The use of other pozzolanic material having better physical properties for promoting the interaction of various compounds such as fly ash was also ineffective because such material possessed undesirable properties such as quick setting before the waste could be uniformly dispersed in such material. Although used as a bonding agent, polymers have not been shown to have successfully bonded most wastes and to be successful, large quantities of the polymer are required. Furthermore, the use of polymeric compounds to promote the solidification is also undesirable because many polymeric compounds themselves are complex and hazardous, the resulting waste compound is toxic and chemical attack, such as sulfate attack, is prompted by such polymers. Also, the resultant waste compound degenerates over time when polymers are used. Thus, such disposal is often not permanent.
The present invention overcomes the deficiencies of the prior methods by providing a unique chemical reagent and a unique process wherein such chemical reagent is mixed with the waste and highly active pozzolanic material to produce a solid product that is non-toxic, safe, strong, smaller in volume than the resultant waste products of previously used solidification processes, easily transportable and easily disposable in landfill or in readily available natural disposal sites such as salt domes and the like. Furthermore, the present invention discloses a chemical reagent and a process utilizing that reagent wherein a pozzolanic waste material is used effectively to dispose of other waste, thus simultaneously disposing of two wastes. The production of the chemical reagent and its application are very simple and economical.
These and other advantages and objectives of the present invention will become apparent from the following description.